Although there are already numerous red dyes on the market for colouring plastics, demand still exists for novel dyes with improved properties. Dyes of different classes of dyes are available which are suitable for colouring plastics in shades of red.
Known soluble red dyes which are used for plastic colouring are, e.g. Solvent Red 135 (Macrolex® Rot EG) (C.I 564120), Solvent Red 179 (Macrolex® Rot E2G) (C.I 564150), Solvent Red 52 (Macrolex® Rot 5B) (C.I. 68210) and Solvent Red 195 (Macrolex® Rot B).
However, the colouristic properties of existing red dyes are not always sufficient for the average technical requirements in the use for colouring plastics. In particular, there is a demand for red dyes for the bulk colouration of plastics which are enhanced with regard to their colour intensity and brilliance, as compared with what is currently available.